AlleleGroup

Overview

AlleleGroup is a marketplace for genomic research data represented as composable NFTs. Built between 2022 and 2023, it uses the ERC-998 standard so a dataset token can own child tokens, which makes it possible to model datasets that contain other datasets and to sell fractions of them.

Why ERC-998

A plain ERC-721 token is a single indivisible asset. Genomic research data does not fit that shape: a study is made of samples, samples belong to cohorts, and a buyer may want a share rather than the whole. ERC-998 composable tokens let a parent NFT hold other NFTs and fungible tokens, so the marketplace can represent:

• Hierarchies: a study token that owns its sample tokens.
• Fractional ownership: fungible shares attached to a dataset token.
• Transfers of whole trees: moving a parent moves everything it owns.

Architecture

┌──────────────────────────────────────────┐
│          React marketplace UI            │
├──────────────────────────────────────────┤
│   Node.js API        │   The Graph       │
│   listings · users   │   subgraph search │
├──────────────────────┴───────────────────┤
│   ethers.js  →  ERC-998 contracts        │
├──────────────────────────────────────────┤
│   IPFS: dataset files & token metadata   │
└──────────────────────────────────────────┘

• Solidity ERC-998 contracts implement composable ownership and marketplace listings.
• IPFS stores dataset files and token metadata off-chain with content-addressed integrity.
• The Graph indexes contract events into a subgraph, which powers search and browsing without scanning the chain.
• React and Node.js deliver the marketplace frontend and the supporting API.

Technologies Used

• Smart Contracts: Solidity, ERC-998
• Indexing: The Graph
• Storage: IPFS
• Chain Integration: ethers.js
• Frontend & API: React, Node.js